2003/10/17 by Dennis P. Clougherty
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Quantum Mechanics and Non-Hermitian Physics #Quantum, superfluid, helium dynamics #cond-mat #physics.atom-ph #quant-ph
paper · pdf · doi:10.1103/physrevlett.91.226105
published as Phys. Rev. Lett. 91, 226105 (2003) · 9 pages, to appear in Phys. Rev. Lett
arxiv created 2003/10/17 · openalex publication_date 2003/11/25 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
It has been stated that for a short-ranged surface interaction, the probability of a low-energy particle sticking to a surface always vanishes as s approximately k with k-->0 where k=sqrt[E]. Deviations from this so-called universal threshold law are derived using a linear model of particle-surface scattering. The Fredholm theory of integral equations is used to find the global conditions necessary for a convergent solution. The exceptional case of a zero-energy resonance is considered in detail. Anomalous threshold laws, where s approximately k(1+alpha),alpha>0 as k-->0, are shown to arise from a soft gap in the weighted density of states of excitations; alpha is determined by the behavior of the weighted density of states near the binding energy.